The major averages pulled back today after the best three rally in over 80 years. The Dow Jones Industrial Average finished down 915 points, or 4.1%, to 21,636. The S&P 500 slid 3.4% to 2,541 while the Nasdaq Composite closed 3.7% lower at 7,502.

Boeing dropped 10.3% to lead the Dow lower. Chevron and Disney each fell more than 8%. Boeing fell after Treasury Secretary Steven Mnuchin said the airplane maker won't seek a government bailout. Procter & Gamble bucked the broader trend after the stock was upgraded to Buy from Hold at Stifel. Energy and tech were the worst-performing sectors in the S&P 500 as they dropped 6.9% and 4.6%, respectively. Energy was pressured by a 4.8% drop in crude prices.

Still, the major averages posted strong gains for the week. The Dow rose 12.8% week to date, its biggest one-week gain since 1938. The S&P 500 gained 10.3% this week for its best weekly performance since March 2009. The Nasdaq also had its biggest weekly gain in 11 years, rising 9.1%.

Global cases of the coronavirus have surged to more than 542,700 with at least 85,996 in the U.S., according to data from Johns Hopkins University. The U.S. has now overtaken China as the country with the most confirmed cases in the world. President Donald Trump held a phone call with Chinese leader Xi Jinping, saying the two countries are "working closely together" to fight the pandemic. Meanwhile, UK Prime Minister Boris Johnson has tested positive for the coronavirus.

U.S. Treasuries ended the week on a higher note, driving yields lower across the curve. The 2-yr yield declined three basis points to 0.23%, and the 10-yr yield declined six basis points to 0.75%. The U.S. Dollar Index declined 1.0% to 98.36. WTI crude lost another 4.2%, or $0.95, settling lower at $21.65/bbl.